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Biomedical subjects

H Nishi

Publications and source records attributed to H Nishi.

At least 55 records · Page 3Linked to original sources
PubMed1999

[Study on the "signal" constituents for the evaluation of animal crude drugs. VI. The identification method of cervi parvum cornu in medicines using DNA analysis].

Cervi Parvum Cornu has been widely used as an agent in commercially available tonic medicines. The establishment of the method for the identification of each agent, especially crude drugs in formulations, is very important from the viewpoint of the quality control of drugs. In this paper, we reported the examination on the extraction method of DNA from the formulations, and also on the PCR method using four sets of primers, amplifying the DNA fragments of the regions of 12S rRNA and/or cytochrome b genes. The same size of DNA fragments as in the Cervi Parvum Cornu reference sample were found in all PCR products obtained from four commercial tonic medicines investigated. Therefore, it was confirmed that Cervi Parvum Cornu was contained in all the tonic medicines used. The PCR method was found to be a useful method for the identification of Cervi Parvum Cornu in tonic medicines and the DNA fragments amplified by the PCR method was clarified to be also helpful materials as index constituents for Cervi Parvum Cornu.

Animals↗
PubMed1999

[Fast drug analysis by capillary electrophoresis. II. Analysis of denopamine tablets. Effects of purity of dimethyl beta-cyclodextrin as chiral selector on enantiomer separations].

Capillary electrophoresis (CE) has been utilized as a tool for enantiomeric separation. It has been incorporated into both USP and EP forums as the methods for general tests and assays. In the present study, we applied CE to the assay and content uniformity of denopamine tablets (KALGUT), which are clinically used as a cardiotonic agent. The electrophoretic solution consisted of phosphate buffer of pH 2.5 containing 2,6-di-O-methyl-beta-cyclodextrin (DM-beta-CD) to achieve enantiomer separation, because denopamine is an optically active drug. During this study, we found that the purity of the positional isomerism of DM-beta-CD, significantly influenced the resolution of denopamine enantiomers. This effect of isomer purity was also confirmed by matrix-assisted laser desorption ionization time-of-flight mass spectrometer analysis. The results of the assay and system suitability test indicated that CE method could be useful as an alternative to the conventional HPLC method.1

Cardiotonic Agents↗
PubMed1999

[Investigation on the marker substances of crude drugs in formulations. I. Marker substances for the identification of astragali radix in kampo and drinkable preparations].

There are few reports about marker substances for the identification of Astragali Radix in formulations. First, constituents analysis was performed by HPLC for the screening of a marker substance, using several lots of Astragali Radix and its fluid extracts. As a result of the analysis, one of the main components was clearly detected even in the fluid extracts, and thought to be a good marker substance. This component was identified to be calycosin (7,3'-dihydroxy-4'-methoxyisoflavone) by the structural analysis. Then, the identification methods of Astragali Radix and its fluid extracts in formulations were investigated with an Astragali Radix extract as a reference standard solution and calycosin as a marker substance. This method was applied to three different kinds of Kampo formulations and three different kinds of drinkable preparations. Consequently, calycosin was clearly detected by a HPLC-multi wavelength detector system, in all investigated formulations. Calycosin will be successfully used as a marker substance for the identification of Astragali Radix and its fluid extracts in formulations.

Chromatography, High Pressure Liquid↗
PubMed1999

Two different P2Y receptors linked to steroidogenesis in bovine adrenocortical cells.

Both extracellular adenosine 5'-triphosphate (ATP) and uridine 5'-triphosphate (UTP) induced corticoid production (steroidogenesis) concentration-dependently in bovine adrenocortical cells (BA cells). Pertussis toxin (PTX, approx. 2 microg/ml) partially inhibited (approx. 55% inhibition) extracellular ATP (100 microM)-induced steroidogenesis in BA cells. However, PTX did not inhibit extracellular UTP (100 microM)-induced steroidogenesis. Both ATP- and UTP-induced steroidogeneses were significantly inhibited by suramin (50-200 microM). These effects were inhibited significantly by reactive blue-2 (more than 100 microM) and pyridoxal-phosphate-6-azophenyl-2',4'-disulphonic acid (more than 100 microM). Both nucleotides (1-100 microM) induced inositol phosphates accumulation and intracellular Ca2+ mobilization, but PTX did not inhibit them. The RT-PCR procedure identified only P2Y2-receptor mRNA in BA cells. These results suggest that extracellular ATP induces steroidogenesis via a unique P2 receptor linked to PTX-sensitive guanine nucleotide-binding protein (G-protein), while extracellular UTP induces steroidogenesis via P2 receptor linked to PTX-insensitive G-protein. Thus, it was concluded that at least two different P2Y-like receptors linking to steroidogenesis exist in BA cells.

Adenosine Triphosphate↗
PubMed1999

Small hepatocellular carcinoma supplied by the right renal capsular artery. A case report.

We present a case of hepatocellular carcinoma (HCC), which was fed only by the right renal capsular artery. Ten years earlier, this patient underwent surgery for a solitary HCC in segment IV. However, the hepatic artery was patent and did not participate in feeding the HCC. We consider the renal capsular artery as an essential extrahepatic parasitic feeding artery to HCC.

Angiography↗
PubMed1999

Mutation and transcription analyses of the p63 gene in cervical carcinoma.

Genetic mutation of p53, which monitors DNA damage and operates cellular checkpoints, is a major factor in the development of human malignancies. A novel gene p63/p73L/p51, encoding a protein with significant homology to p53 and p73, was recently identified at 3q27-9. To investigate the penetration of p63 in cervical carcinogenesis, mutation and transcription analyses of p63 were performed in cervical carcinoma. A certain isotype of p63 called TAp63gamma encodes the acidic N-terminus and possesses a short C-terminus. Using reverse transcriptase-polymerase chain reaction-single strand conformation polymorphism (RT-PCR-SSCP) analysis for TAp63gamma, one mutation was found in the cervical carcinoma cell line SKG-I. However, no mutations causing amino acid substitutions or frameshifts were found in 54 cases examined for TAp63gamma, which is thought to be a tumor suppressor gene. While cervical carcinomas tended to yield a positive signal in the RT-PCR reaction designed to amplify transcripts encoding the acidic N-terminus, normal cervix and cervical intraepithelial neoplasia (CIN) did not express this transcript. These data suggest that the p63 gene does not play an essential role as a tumor suppressor gene, but expression of TAp63gamma may be speculatively associated with tumor growth in cervical carcinogenesis.

Adenocarcinoma↗
PubMed1999

[Mediastinoscopic resection combined with a sternum lift technique in a case of thymic cyst].

We report on a case of thymic cyst which was successfully treated with mediastinoscopic resection combined with a sternum lift technique. A 62-year-old man was admitted to our hospital with a thymic cyst, which was causing chest discomfort and was increasing in size. The tumor was located above the pulmonary artery in the anterior mediastinum. He underwent mediastinoscopic resection while lifting the inferior portion of the sternum with a Laparolift. The cyst was resected sharply and bluntly with the Harmonic Scalpel without rupture. The patient was discharged on the 6th postoperative day in a good condition. Mediastinoscopic resection of a thymic cyst through a xiphoid approach is a useful surgical approach because of the absence of postoperative pain and because it allows early discharge from the hospital.

Endoscopy↗
PubMed1999

[A case report of gastric carcinoma with complete remission of paraaortic lymph node metastasis by 5'-DFUR and MMC administration after resection of primary tumor].

A 53-year-old man was referred to our hospital with Borrmann type 2 advanced gastric cancer with a Virchow's node metastasis. A CT scan revealed a paraaortic lymph node metastasis. Because the tumor was diagnosed as being a poor candidate for curative resection, only a total gastrectomy was done. After surgery, administration of 5'-DFUR and MMC was begun. As a result, the paraaortic lymph node metastasis disappeared and the Virchow's node metastasis was reduced. The patient is well with no sign of recurrence 20 months after the operation.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1998

Expression of proto-oncogenes and gene mutation of sarcomeric proteins in patients with hypertrophic cardiomyopathy.

Several mutations of cardiac beta-myosin heavy chain (beta-MHC) gene were reported in patients with hypertrophic cardiomyopathy (HCM). Involvement of proto-oncogenes has been shown in the mechanism of experimental cardiac hypertrophy. This study sought to examine the effects of c-H-ras and c-myc expression in the steady-state myocardium on hypertrophic changes and to evaluate the possible interaction between beta-MHC mutation and proto-oncogene expression in HCM. Endomyocardial biopsy was performed in 17 HCM patients (5 beta-MHC mutations and 1 troponin T mutation) and 7 control subjects (no mutation). Reverse transcription-polymerase chain reaction analysis revealed c-H-ras expression in all members of both groups. Cardiomyocyte size was correlated with the expression level of c-H-ras (P<0.001), and c-H-ras expression was upregulated in HCM patients (P<0.01). HCM patients with a beta-MHC mutation had the higher c-H-ras expression than did control subjects or patients without a mutation (P<0.01). c-myc mRNA was expressed in 7 of 17 HCM patients but not in control subjects. Myocyte size was greater in c-myc-positive HCM patients than in control subjects and c-myc-negative HCM patients (P<0.001 and P<0.05, respectively). The proto-oncogene expression did not affect clinical findings, myocardial fibrosis, or disarray. In conclusion, c-H-ras and c-myc expression in the steady-state myocardium may play a role in the hypertrophic mechanism in HCM. It is possible that ss-MHC gene mutation has some effect on the regulation of proto-oncogene expression in HCM.

Adolescent↗
PubMed1998

[Study on the "signal" constituents for the evaluation of animal crude drugs. V. The "signal" constituents for the identification of Lumbricus in cold medicines].

Lumbricus has been widely used as an antifebrile agent in cold medicines. The identification of each agent, especially crude drugs in formulations, is very important from the viewpoint of quality control. In this paper, the contents of amino acids, organic acids, nucleic acid components and cholesterol were investigated to evaluate the "signal" constituents of Lumbricus and Lumbricus extracts in the medicines. It was found that the content pattern of these components of Lumbricus extracts was almost the same as those in Lumbricus itself. However, most of other crude drugs used in cold medicines, also contain some of these components. It was difficult to identify Lumbricus through the difference in the content pattern of these components. Therefore, we focused on such five constituents as cholesterol, lombricine, lactic acid, inosine and hypoxanthine, because lombricine is a characteristic amino acid of Lumbricus and the contents of other four components in Lumbricus are relatively high compared with those of other crude drugs. Lombricine and inosine were detected clearly in all seven commercial formulations investigated, and cholesterol and hypoxanthine were also detected except two commercial formulations. However, the detection of lactic acid was not successful in all formulations, because of the presence of interfering components. In the seven commercial cold medicines, lombricine and inosine were found to be useful as "signal" constituents for the identification of Lumbricus in cold medicines.

Analgesics, Non-Narcotic↗
PubMed1998

Comparison of telomerase activity in normal chorionic villi to trophoblastic diseases.

Trophoblasts are derived from the normal placenta, and they infiltrate into the endometrium and the maternal blood vessels under strict control but, unlike malignant cells, never metastasize. To understand the proliferative characteristics of trophoblasts and its related disorders, we assessed telomerase activity in chorionic villi obtained from 27 normal individuals, 9 hydatidiform moles, and 2 choriocarcinomas. Telomerase activity was detected in 13/27 (48%) normal chorionic villi samples. The detectability and the level of telomerase activity depended on gestational age; 8/10 (80%) villi samples in the first trimester (relative telomerase activity; 1.77 +/- 1.37), whereas 2/8 (25%) villi samples in the second trimester (0.78 +/- 1.52) and 3/9 (33%) in the third trimester (0.28 +/- 0.43) had telomerase activity. Telomerase activity of normal chorionic villi in the first trimester was higher than that of the third trimester (P = 0.0251). In contrast, all mole samples had increased telomerase activity compared to normal villi (3.17 +/- 2.81, P = 0.0152). Thus, a relationship may exist among cell proliferation, telomerase activity, and progression to trophoblastic disease.

Adult↗
PubMed1998

Possible mechanism of painful radiculopathy in lumbar disc herniation.

The pathophysiologic mechanisms of painful radiculopathy caused by a herniated intervertebral disc remain unknown. This study sought to determine whether the autologous intervertebral disc produces pain related behavior and whether phospholipase A2 and nitric oxide are involved in the pathophysiologic mechanism producing the behavior. A rat model, in which autologous intervertebral discs were implanted on the nerve root in the lumbar spine, was used to measure hyperalgesia, which is a pain related behavior in the rat. In this experimental model, autologous nucleus pulposus and anulus fibrosus transplanted to lumbar nerve roots produced mechanical and thermal hyperalgesia, respectively. Epidural injection of a selective inhibitor for phospholipase A2 resulted in the disappearance of hypersensitivity to noxious mechanical stimuli. Thermal hyperalgesia produced by application of the anulus fibrosus was abated and abolished by epidural injections of saline and one of the inhibitors for nitric oxide synthase, respectively. The authors suggest that chemical mediators such as phospholipase A2 and nitric oxide, induced by extruded or sequestrated intervertebral discs, are involved in the pathophysiologic mechanisms of painful radiculopathy in lumbar disc herniations. This study may be useful in attempting to develop new medical approaches for treatments of lumbar disc herniation.

Analysis of Variance↗
PubMed1997

Enantioselectivity in chiral capillary electrophoresis with polysaccharides.

This review surveys enantiomer separation by capillary electrophoresis (CE) using polysaccharides as chiral selectors. Many ionic or electrically neutral polysaccharides, such as heparin, chondroitin sulfate, dextrin, etc., have been employed successfully for the CE separation of enantiomers. The operational conditions that affect the enantioselectivity of the chiral separation system will be described. The mechanism of enantioseparation will also be discussed briefly.

Cyclodextrins↗
PubMed1997

Reduced blood accumulation of biotinylated monoclonal antibody A7 after the subsequent administration of avidin.

Clear immunoscintigraphy with radiolabeled monoclonal antibodies (MAbs) requires a high tumor tissue/blood ratio of radioactivity. In this study, we attempted to obtain a high tumor tissue/blood ratio by the active removal of radiolabeled MAb from the circulation, using the avidin-biotin system. Biotinylated 125I-labeled MAb A7 was injected intravenously into nude mice bearing a human colon cancer (WiDr) xenograft. Avidin was injected 24 h later. The tumor tissue/blood ratio of radioactivity was almost four times that of controls. These results suggest that biotinylated 125I-labeled MAb A7 and avidin are potentially useful for the rapid immunodetection of human colon cancer.

Animals↗
PubMed1997

Pharmaceutical applications of micelles in chromatography and electrophoresis.

This review surveys the use of micelles as separation media in chromatography and electrophoresis. Applications to pharmaceuticals whose molecular masses are relatively small are focused on in this review. In high-performance liquid chromatography (HPLC), chromatography using micelles and reversed-phase stationary phases such as octadecylsilylized silica gel (ODS) columns is known as micellar liquid chromatography (MLC). The main application of MLC to pharmaceutical analysis is the same as in ion-pair chromatography using alkylsulfonate or tetraalkylammonium. In most cases, selectivity is much improved compared with other short alkyl chain ion-pairing agents such as pentanesulfonate or octanesulfonate. Direct plasma/serum injection can be successful in MLC. Separation of small ions is also successful by using gel filtration columns and micellar solutions. In electrophoresis, especially capillary electrophoresis (CE), micelles are used as pseudo-stationary phases in capillary zone electrophoresis (CZE). This mode is called micellar electrokinetic chromatography (MEKC). Most of the drug analysis can be performed by using the MEKC mode because of its wide applicability. Enantiomer separation, separation of amino acids and closely related peptides, separation of very complex mixtures, determination of drugs in biological samples etc. as well as separation of electrically neutral drugs can be successfully achieved by MEKC. Microemulsion electrokinetic chromatography (MEEKC), in which surfactants are also used in forming the microemulsion, is successful for the separation of electrically neutral drugs as in MEKC. This review mainly describes the typical applications of MLC and MEKC for the analysis of pharmaceuticals.

Amino Acids↗
PubMed1997

Histochemical demonstration of nitric oxide in herniated lumbar discs. A clinical and animal model study.

STUDY DESIGN: This study was designed to localize the cells that produce nitric oxide in a lumbar disc herniation by histochemical method, including in situ hybridization. OBJECTIVE: To clarify which cells in herniated lumbar discs produce nitric oxide. SUMMARY OF BACKGROUND DATA: It was reported that herniated lumbar intervertebral disc specimens in culture are capable of producing nitric oxide. METHODS: Surgical specimens from lumbar disc herniation were examined to determine nitric oxide synthase histologically using nicotinamide adenine dinucleotide phosphate diaphorase histochemistry. Allografts of intervertebral disc materials were placed on the epidural space at L6 level in the rat. Nitric oxide synthase was examined in the applied tissues using nicotinamide adenine dinucleotide phosphate diaphorase histochemistry and in situ hybridization histochemistry. RESULTS: Nicotinamide adenine dinucleotide phosphate diaphorase (nitric oxide synthase) positive cells were observed in 2 (40%) of 5 herniated disc materials in patients. The positive cells were mainly in granulation tissue around intervertebral disc materials. In animal models, nitric oxide synthase-positive cells were observed in all specimens at 1 and 2 weeks postoperatively. Newly formed vessels and small round cells in granulation tissue around the grafted intervertebral disc showed positive reaction. In situ hybridization demonstrated the expression of inducible isoform of nitric oxide synthase messenger RNA (mRNA) identical to small round cells around the applied intervertebral disc. CONCLUSION: Nitric oxide in a lumbar disc herniation is mainly produced by cells in granulation tissue around the herniated intervertebral disc.

Adult↗
PubMed1997

Enantiomer separation of denopamine by capillary electrophoresis with charged and uncharged cyclodextrins.

Direct separation of enantiomers of denopamine was investigated by capillary electrophoresis employing charged and uncharged cyclodextrin (CD) derivatives. Uncharged beta-type CDs, having hydrophobic groups, were essential for the enantioseparation of denopamine; of these, especially dimethyl-beta-CD was effective. Among charged CDs, gamma-type as well as beta-type CDs were found effective for the enantioseparation of denopamine. Reversal of migration order of R-form (active) and S-form enantiomers was investigated by using two types of coated capillaries: (i) an amine capillary with an inner wall coated with dimethylamino groups, and (ii) a polyacrylamide-coated capillary. Manipulation of migration order could be easily performed by selecting suitable capillaries, buffer pH, and CDs.

Cyclodextrins↗